Prophylactic effect of JTE-607 on LPS-induced acute lung injury in rats with CINC-1 inhibition

Characterization of acute lung injury in the bleomycin rat model

The aim of this study was to describe and characterize the pathophysiological changes occurring during the early inflammatory phase (first 3 days) in the rat bleomycin model of lung injury preceding the development of fibrosis. Further, we wanted to understand the kinetics and factors contributing to bleomycin-induced acute lung injury (ALI) and provide a robust, reliable and reproducible framework of features of ALI readouts to assess effects of therapeutics on bleomycin-induced ALI in rats. We induced ALI in rats with intratracheal (i.t.) installation of bleomycin. The animals were sacrificed on predetermined time points, that is, Day 0, 1, 2, and 3 post the bleomycin challenge. We analyzed bronchoalveolar lavage fluid (BALF) and lung tissue to establish and assess relevant experimental features of ALI. We demonstrated that bleomycin induced key features of experimental ALI including a profound increase in neutrophils in BALF (50-60%), pulmonary edema, and lung pathology on Day 3 after challenge. Furthermore, we showed that TGF-β1, IL-1β, TNF-α, IL-6, CINC-1, TIMP-1, and WISP-1 were induced by studying their kinetic profile during the first 3 days after bleomycin injury consistent with their known role ALI. We also confirmed that detectable fibrogenesis occurs at the earliest on Day 3 after injury based on collagen content, along with changes in the TGF-β/Smad signaling pathway and increased expression of Galectin-3, Vimentin, and Fibronectin in lung homogenate. Our report presents robust features and contributing mediators/factors to the pathology of bleomycin-induced ALI in rats on Day 3. The kinetic data provide insights on the progression of ALI and a detailed understanding of early events before actual fibrosis development. This set of experimental endpoints is very appropriate and invaluable for efficacy testing of potential novel therapeutic treatments (single or combined) in ALI and understanding their mechanism of action.

Anti‑inflammatory effect of salusin‑β knockdown on LPS‑activated alveolar macrophages via NF‑κB inhibition and HO‑1 activation

Inflammation of alveolar macrophages is the primary pathological factor leading to acute lung injury (ALI), and NF-κB activation and HO-1 inhibition are widely involved in inflammation. Salusin-β has been reported to contribute to the progression of the inflammatory response, but whether salusin-β could regulate inflammation in lipopolysaccharide (LPS)-induced ALI remains unknown. The present study aimed to investigate the role of salusin-β in LPS-induced ALI and to uncover the potential underlying mechanisms. Sprague-Dawley rats were subjected to LPS administration, and then pathological manifestations of lung tissues, inflammatory cytokines levels in bronchoalveolar lavage fluid (BALF) and expression of salusin-β in macrophages of lung tissues were assessed. NR8383 cells with or without salusin-β knockdown were treated with LPS, and then the concentration of inflammatory cytokines, and the expression of high mobility group box-1 (HMGB1), NF-κB signaling molecules and heme oxygenase-1 (HO-1) levels were detected. The results showed that LPS caused injury of lung tissues, increased the levels of proinflammatory cytokines in BALF, and led to higher expression of salusin-β or macrophages in lung tissues of rats. In vitro experiments, LPS also upregulated salusin-β expression in NR8383 cells. Knockdown of salusin-β using short hairpin (sh)RNA inhibited the LPS-induced generation of inflammatory cytokines. LPS also enhanced HMGB1, phosphorylated (p)-IκB and p-p65 expression, but reduced HO-1 expression in both lung tissues and NR8383 cells, which were instead inhibited by the transfection of sh-salusin-β. In addition, knockdown of HO-1 using shRNA reversed the inhibitory effect of sh-salusin-β on the LPS-induced generation of inflammatory cytokines, activation of NF-κB signaling and inactivation of HO-1. In conclusion, this study suggested that knockdown of salusin-β may inhibit LPS-induced inflammation in alveolar macrophages by blocking NF-κB signaling and upregulating HO-1 expression.

The novel multi-cytokine inhibitor TO-207 specifically inhibits pro-inflammatory cytokine secretion in monocytes without affecting the killing ability of CAR T cells

Cancer immunotherapy using chimeric antigen receptor–armed T (CAR T) cells have been shown to improve outcomes significantly in patients with hematological malignancies. However, cytokine release syndrome (CRS) remains a risk. CRS is characterized by the excessive activation of CAR T cells and macrophages. Signs and symptoms of CRS are usually resolved after steroid administration, but steroids abrogate the expansion and persistence of CAR T cell populations. Tocilizumab is a humanized monoclonal antibody (mAb) that attenuates CRS without significant loss of CAR T cell activity. However, interleukin-6 (IL-6)/IL-6 receptor (IL-6R) blockade alone cannot relieve CRS symptoms fully, and novel treatments are needed to prevent or cure CRS. TO-207 is an N-benzoyl-L-phenylalanine derivative that significantly inhibits inflammatory cytokine production in human monocyte and macrophage-specific manner. We investigated whether TO-207 could inhibit cytokine production without impairing CAR T cell function in a CRS-simulating co-culture system.

Effects of a cytokine inhibitor, JTE-607, on the response to endotoxin in healthy human volunteers

It is generally regarded that the excessive production of cytokines plays an important role in the pathology of autoimmune diseases and septic shock. We have investigated the ability of JTE-607, a novel inhibitor of cytokine production, to modulate the inflammatory response to endotoxin in healthy human volunteers. Three cohorts of healthy male volunteers were recruited for a randomized, placebo-controlled, double-blind study. Within each cohort, 6 subjects received a single 8-hour intravenous infusion of JTE-607 (either 0.03, 0.1 or 0.3 mg/kg/h) and 3 subjects received a placebo infusion. Two hours after the start of the JTE-607 infusion, all subjects received a 30 unit/kg bolus infusion of endotoxin. JTE-607 administration resulted in the decrease in endotoxin-induced IL-10 production with mean % difference from placebo of -79.5% (P=0.040) and -86.2% (P=0.026) at 0.1 and 0.3 mg/kg/h dose, respectively. The production of endotoxin-mediated interleukin (IL)-1 receptor antagonist was significantly inhibited at 0.3 mg/kg/h dose with mean % difference from placebo of -60% (P=0.0037). Endotoxin-induced C-reactive protein decreased with the increasing dose of JTE-607 with mean % difference from placebo of -32.1% (P=0.322), -82.9% (P=0.0001) and -90.3% (P<0.0001) at 0.03, 0.1 and 0.3 mg/kg/h dose, respectively. In conclusion, this study describes a cytokine modulator JTE-607, which inhibits production of IL-10, IL-1ra and C-reactive protein in a human model of endotoxemia.

Effects of SA13353, a transient receptor potential vanilloid 1 agonist, on leukocyte infiltration in lipopolysaccharide-induced acute lung injury and ovalbumin-induced allergic airway inflammation

We recently demonstrated that SA13353, a transient receptor potential vanilloid 1 (TRPV1) agonist, reduced the severity of the symptoms of kidney injury, arthritis, and encephalomyelitis in disease models. Here, we investigated the effects of orally administered SA13353 on leukocyte infiltration in lipopolysaccharide (LPS)-induced acute lung injury and ovalbumin-induced allergic airway inflammation. In LPS-induced lung injury, SA13353 attenuated neutrophil infiltration and the increase of TNF-alpha and CINC-1 levels. In allergic airway inflammation, SA13353 tended to inhibit leukocyte infiltration and attenuated the increase of IL-4 and IL-12p40. These results suggest that somatosensory TRPV1 may play an anti-inflammatory role in lung inflammation.

Anti-apoptotic PTD-FNK protein suppresses lipopolysaccharide-induced acute lung injury in rats

The present study was aimed at clarifying the effects of an anti-apoptotic protein for modulating symptoms in acute lung injury (ALI). From Bcl-x(L), a Bcl-2 family member, we constructed an artificial protein (FNK) and fused it with the protein transduction domain (PTD) of the HIV/Tat protein (PTD-FNK) to facilitate its permeation into cells. ALI was induced by intratracheal infusion of lipopolysaccharide (LPS) into Sprague-Dawley male rats. PTD-FNK was injected into the peritoneal cavity of the animals either 2 h before, or 3 h or 6 h after LPS challenge. All rats were sacrificed 24 h after the last treatment. Cell differential ratios and albumin concentration were estimated in bronchoalveolar lavage fluid. We examined histological change, myeloperoxidase activity, TUNEL assay, caspase-3/caspase-3-like activity and immunohistochemical reaction for caspase 3 (active form). In animals with PTD-FNK treatment, the albumin leakage was significantly attenuated with protection of tissue damage. Also, the apoptosis of alveolar wall cells was reduced by PTD-FNK treatment, while a total cell number and the neutrophil ratio were not changed. Human umbilical vein endothelial cells (HUVEC) and cells of an alveolar epithelial cell line (A549) were exposed to LPS or TNF-alpha with or without PTD-FNK treatment in vitro. Cell survival rates examined by trypan-blue exclusion assay were increased by PTD-FNK treatment in a concentration-dependent manner. Thus, PTD-FNK could play a protective role in ALI by suppressing apoptosis of alveolar epithelial cells and capillary endothelial cells despite of some effect on neutrophil activity.

Protective effect of curcumin on endotoxin-induced acute lung injury in rats

To investigate the protective effect of curcumin on endotoxin-induced acute lung injury in rats, and explore the underlying mechanisms, 24 male Wistar rats were randomly divided into 4 experimental groups: sham-vehicle (S), sham-curcumin (C), lipopolysaccharide (LPS)-vehicle (L), and curcumin-lipopolysaccharide (C-L) groups. The wet/dry (W/D) weight ratio of the lung and bronchoalveolar lavage (BAL) fluid protein content were used as measures of lung injury. Neutrophil recruitment and activation were evaluated by BAL fluid cellularity and myeloperoxidase (MPO) activity in cell-free BAL and lung tissue. The levels of cytokine-induced neutrophil chemoattractant-I (CINC-1) in lung tissues were measured by ELISA. The histopathological changes of lung tissues were observed by using the HE staining. Our results showed that lung injury parameters, including the wet/dry weight ratio and protein content in BALF, were significantly higher in the L group than in the S group (P<0.01). In the L group, higher numbers of neutrophils and greater MPO activity in cell-free BAL and lung homogenates were observed when compared with the S group (P<0.01). There was a marked increase in CINC-1 levels in lung tissues in response to LPS challenge (P<0.01, L group vs S group). Curcumin pretreatment significantly attenuated LPS-induced changes in these indices. LPS caused extensive morphological lung damage, which was also lessened after curcumin pretreatment. All the above-mentioned parameters in the C group were not significantly different from those of the S group. It is concluded that curcumin pretreatment attenuates LPS-induced lung injury in rats. This beneficial effect of curcumin may involves, in part, inhibition of neutrophilic recruitment and activity, possibly through inhibition of lung CINC-1 expression.

A novel, potent dual inhibitor of the leukocyte proteases cathepsin G and chymase: molecular mechanisms and anti-inflammatory activity in vivo

Certain leukocytes release serine proteases that sustain inflammatory processes and cause disease conditions, such as asthma and chronic obstructive pulmonary disease. We identified beta-ketophosphonate 1 (JNJ-10311795; RWJ-355871) as a novel, potent dual inhibitor of neutrophil cathepsin G (K(i) = 38 nm) and mast cell chymase (K(i) = 2.3 nm). The x-ray crystal structures of 1 complexed with human cathepsin G (1.85 A) and human chymase (1.90 A) reveal the molecular basis of the dual inhibition. Ligand 1 occupies the S(1) and S(2) subsites of cathepsin G and chymase similarly, with the 2-naphthyl in S(1), the 1-naphthyl in S(2), and the phosphonate group in a complex network of hydrogen bonds. Surprisingly, however, the carboxamido-N-(naphthalene-2-carboxyl)piperidine group is found to bind in two distinct conformations. In cathepsin G, this group occupies the hydrophobic S(3)/S(4) subsites, whereas in chymase, it does not; rather, it folds onto the 1-naphthyl group of the inhibitor itself. Compound 1 exhibited noteworthy anti-inflammatory activity in rats for glycogen-induced peritonitis and lipopolysaccharide-induced airway inflammation. In addition to a marked reduction in neutrophil influx, 1 reversed increases in inflammatory mediators interleukin-1alpha, interleukin-1beta, tissue necrosis factor-alpha, and monocyte chemotactic protein-1 in the glycogen model and reversed increases in airway nitric oxide levels in the lipopolysaccharide model. These findings demonstrate that it is possible to inhibit both cathepsin G and chymase with a single molecule and suggest an exciting opportunity in the treatment of asthma and chronic obstructive pulmonary disease.

JTE-607, a cytokine release blocker, attenuates acid aspiration-induced lung injury in rats

The present study was designed to clarify the effects of (-)-ethyl N-[3,5-dichloro-2-hydroxy-4-[2-(4-methyl-piperazin-1-yl)ethoxy]benzoyl]-l-phenylalaninate dihydrochloride (JTE-607), a novel multiple cytokine inhibitor, on hydrochloric acid (HCl) aspiration lung injury in rats. HCl (0.1 N, 2 ml kg(-1)) was instilled into male Sprague-Dawley rats that were pretreated with or without JTE-607 (30 or 75 mg kg(-1) h(-1)). As a control, normal saline (2 ml kg(-1)) was instilled in rats. All the animals were anesthetized with intraperitoneally injected pentobarbital sodium (40 mg kg(-1)). Bronchoalveolar lavage was performed 5 h (h) after HCl or normal saline instillation. In bronchoalveolar lavage fluid, the increases in total nuclear cell counts, neutrophil counts, optical density at 412 nm as an indication of pulmonary hemorrhage, concentrations of albumin, tumor necrosis factor (TNF)-alpha, interleukin (IL)-6 and cytokine-induced neutrophil chemoattractant induced by HCl instillation were significantly reduced by JTE-607 pretreatment. The level of expression of tumor necrosis factor-alpha and interleukin-6 mRNA in lung tissue was analyzed. The mean expression level of tumor necrosis factor-alpha and interleukin-6 mRNA in the JTE-607 group was lower than that in the HCl and NS groups. The wet-to-dry weight ratio was also determined, and JTE-607 at the dose of 75 mg kg(-1) h(-1) significantly attenuated the increased wet-to-dry weight ratio induced by HCl. These results suggest that JTE-607 can inhibit the production of inflammatory cytokines such as tumor necrosis factor-alpha, interleukin-6 and cytokine-induced neutrophil chemoattractant and attenuate acid-induced lung injury in rats. This agent might be therapeutically useful for lung injury.

Comparative study of glucocorticoids, cyclosporine A, and JTE-607 [(-)-Ethyl-N[3,5-dichloro-2-hydroxy-4-[2-(4-methylpiperazin-1-yl)ethoxy]benzoyl]-L-phenylalaninate dihydrochloride] in a mouse septic shock model

Actions of glucocorticoids, cyclosporine A, and JTE-607 [(-)-ethyl-N-[3,5-dichloro-2-hydroxy-4-[2-(4-methylpiperazin-1-yl)ethoxy]benzoyl]-L-phenylalaninate dihydrochloride], a proinflammatory cytokine inhibitor that does not inhibit interleukin (IL)-2 or interferon-gamma, were compared in a mouse septic shock model induced by cecal ligation and puncture (CLP). CLP caused elevation of macrophage inflammatory protein (MIP)-2 in lung, and MIP-2 and IL-6 in plasma and peritoneal fluid, reaching a peak 4 to 8 h after CLP. Myeloperoxidase (MPO) activity in lung increased and reached a peak 8 to 12 h after CLP. Acute treatment (subcutaneous injections 1 h before and 2 h after CLP) of mice with JTE-607 and methylprednisolone showed significant inhibition of elevated cytokine levels and MPO activity, plus increased survival rate. Similar treatment with cyclosporine A and prednisolone was ineffective. Chronic treatment (subcutaneous injection for seven consecutive days before CLP) of mice with JTE-607 also showed an inhibitory effect on cytokine production, MPO activity and mortality. In contrast, chronic treatment with cyclosporine A and prednisolone did not inhibit cytokine production or MPO activity, but rather exacerbated mortality. These results indicate that JTE-607 has protective effect on mouse mortality induced by CLP, correlating with inhibition of proinflammatory cytokines, whereas the immunosuppressants cyclosporine A and prednisolone do not. This suggests that JTE-607, a multiple cytokine inhibitor that does not cause adverse immunosuppression, is useful for treatment of septic shock.

Pharmacologic preconditioning of JTE-607, a novel cytokine inhibitor, attenuates ischemia-reperfusion injury in the myocardium

BACKGROUND

Myocardial ischemia-reperfusion injury is a main cause of postoperative cardiac dysfunction, and a burst of proinflammatory cytokines, such as tumor necrosis factor alpha, interleukin 1 beta, interleukin 6, and interleukin 8, plays a pivotal role. Recently, JTE-607 has been reported as a potent inhibitor of the multiple inflammatory cytokines in the endotoxin shock mouse model. In this study we proved the hypothesis that JTE-607 might attenuate myocardial ischemia-reperfusion injury in a rat model.

METHODS

The isolated rat hearts in the JTE-607 preconditioning group (J group, n = 8) or control group (C group, n = 8) were subjected to warm ischemia (37 degrees C) for 30 minutes, followed by 60 minutes of reperfusion with the Langendorff perfusion system.

RESULTS

Left ventricular developed pressure and maximum dp/dt after reperfusion were significantly improved in the J group than in the C group (P <.01). Creatine phosphokinase leakage is significantly lower in the J group (P <.05). Moreover, the tissue cytokine levels, such as tumor necrosis factor alpha, interleukin 6, and interleukin 8, in the myocardium were significantly lower in the J group than in the C group (P <.05).

CONCLUSION

These results suggested that the pharmacologic preconditioning of JTE-607 inhibits a burst of endogenous cytokines in the myocardium, resulting in the improvement of cardiac function after ischemia-reperfusion injury. Thus JTE-607 might be a novel therapeutic strategy for the protection of postoperative cardiac dysfunction in cardiac surgery.

CINC-1 is an acute-phase protein induced by focal brain injury causing leukocyte mobilization and liver injury

Following injury or infection, the liver releases acute-phase proteins (APP). After a severe focal injury, this systemic response can be excessive and may lead to multiorgan dysfunction (MODS). CINC-1 is a neutrophil chemoattractant, and we have now established that it also functions as an early APP after injury to the brain or to peripheral tissues. After induction of a focal inflammatory lesion in the brain, there is rapid hepatic and serum CINC-1 induction, which is associated with increases in neutrophil numbers within the liver and within the circulation. CINC-1-mediated recruitment of neutrophils to organs distant from the primary injury site may contribute to MODS. Indeed, we found that enzyme markers of liver tissue injury are increased in the serum following generation of a focal inflammatory lesion in the brain. Neutralization of CINC-1 in the periphery reversed brain-injury-induced neutrophil mobilization and inhibited recruitment of neutrophils to the brain and to the liver. Thus, a significant component of the hepatic acute-phase response is the release of chemokines by the liver, which act to amplify the inflammatory response and modulate the subsequent leukocytosis and secondary tissue damage. Hepatic CINC-1 synthesis following injury presents a novel focus for treatment of inflammation.